Caudal Kidney Research Articles

Ultrasonographic technique and appearance of the coelomic organs in crocodilians

IntroductionCrocodilians have significant ecological, conservational, and economic roles. They are also commonly raised for commercial purposes and kept as zoological specimens. Although ultrasonography has been used in zoological contexts for health assessments of crocodilians, published studies on a detailed ultrasonography protocol and ultrasonographic anatomy are lacking. This study aimed to establish a standardized ultrasonography protocol and pictorial reference of the ultrasonographic appearances of the coelomic organs of crocodilians.MethodsA total of 7 crocodilians comprising 4 different species were included in this study. The crocodilians were manually restrained and underwent a non-contrasted and contrasted computed tomography (CT) scan, followed by an ultrasonography (USG) examination. Ultrasound fusion imaging technique enabled greater confidence in establishing a clear organ localization and correlation between modalities by visualizing the same anatomy from the same view angle.ResultsThe heart, caudal vena cava, liver, fat body (steatotheca), spleen, stomach, duodenal loops, pancreas, kidneys, testes, ovaries and cloaca were visualized in all species. Longitudinal and transverse images of the coelomic structures were acquired when possible. The ultrasonographic characteristics of the coelomic organs, including transducer positioning, acoustic window and approach, shape, size, marginations, and echo pattern were documented.DiscussionThe findings of this study provided a useful ultrasonographic protocol and anatomical reference of the coelomic organs in crocodilians. Invaluable insights into the practicality and adequacy of ultrasonography in evaluating the coelomic structures of crocodilians as part of health assessment and disease diagnosis were also discussed.

GROSS AND ULTRASONOGRAPHIC ANATOMY OF THE COELOMIC ORGANS OF HEALTHY AXOLOTLS (AMBYSTOMA MEXICANUM).

The objectives of this study were to describe the gross anatomy and ultrasonographic appearance of coelomic organs in subadult and adult axolotls (Ambystoma mexicanum), to describe an ultrasound technique, and to test correlations of ultrasonographic measurement with body length, width, and weight. Necropsies of coelomic organs were conducted on 10 axolotls (females = 5; males = 5) and ultrasound on 11 (males = 5; females = 6). Animals were kept in water and maintained conscious during ultrasound. The heart, caudal vena cava, liver, gallbladder, spleen, esophagus, stomach, colon, kidneys, ovaries, and fat bodies were identified in all study subjects, although testicles were identified in only 6/7 subjects. The pancreas and adrenal glands could not be identified in any animals, either during necropsy or ultrasonography. Coelomic and pericardial effusion was present in all animals. Ultrasonographic measurements of the liver, spleen, myocardial thickness, and right and left kidney length were highly repeatable (correlation value [CV] < 5%) and the esophagus, spleen, caudal vena cava, fat bodies, gallbladder, colon thickness, right kidney height and width, and right testicle diameter were statistically repeatable (CV < 10%).

Abdominal ultrasound features and reference values in healthy guinea pigs (Cavia porcellus).

This study aimed to determine the ultrasonographic features and reference values of the abdominal anatomy in guinea pigs. A complete abdominal ultrasonographic examination was performed in 20 adults and 20 young guinea pigs. The thickness of the wall of the gallbladder, stomach, duodenum, caecum, colon and urinary bladder (UB) was measured. Also, the adrenal glands (AGs) (width of the cranial and caudal poles, length), kidneys (length, width, height), ovaries (length, width), testes (length, width), uterus (width) and seminal glands (width) and the thickness of the spleen and pancreas were measured. All the measurements were compared between age groups and sexes. The liver, gallbladder, gastrointestinal tract, pancreas, spleen, kidneys, UB, AGs and great vessels were clearly visualised in all the guinea pigs. No significant statistical differences were found between the sexes, but there were statistically significant differences in the size of the kidneys, AGs, pancreas, spleen and reproductive organs between age groups. No significant differences in the wall thickness of the digestive system, gallbladder and UB were observed between groups. The main limitation of this study is the lack of gross anatomical or histological correlation. The results of this study support the use of ultrasonography as a diagnostic tool in guinea pigs and provide reference values for the abdominal organs of this species.

Total mercury content in selected tissues of common carp (Cyprinus carpio) pond farmed in the Czech Republic

The aim of this study was to evaluate the total mercury content in selected tissues (muscle, spleen, kidney, liver, scales, brain and gonads) of common carp (Cyprinus carpio). Thirty individuals of market carp caught in three ponds (Jaroslavicky, Strachotin, Vrkoc) located in the Morava River basin in the Czech Republic were used for this study. Total mercury was determined by atomic absorption spectrometry on AMA 254 device. The highest total mercury content was found in the muscle of carp (7.6 ± 2.8 µg·kg-1 in Jaroslavicky, 6.8 ± 2.3 µg·kg-1 in Vrkoc, and 12.9 ± 4.3 µg·kg-1 in Strachotin), followed by levels in caudal kidney, liver, spleen, and brain; the lowest mercury content was determined in gonads and scales. The comparison revealed that individual localities significantly differ in the mercury content in muscle, caudal kidney, liver and spleen samples. However, in all cases the values of the mercury content in muscle complied with the hygienic limit of up to 0.3 mg·kg-1, which means that mercury does not pose a risk to the consumers of these pond farmed fish and that the benefits of eating fish meat outweigh the potential risk in terms of mercury content.

Morphological and histometric features of the caudal kidney in piranha Pygocentrus nattereri (Characiformes: Serrasalmidae)

Abstract Pygocentrus nattereri is a widely distributed species in the Neotropical region and a potential bio-indicator. Kidneys have functions in fish physiology, allowing them to live in different environments. We aimed to compare the histological characteristics of caudal kidneys between males and females, associating them with the renosomatic index (RSI). For this purpose, 15 males and 14 females were used for biometric and histological analyses. Structural volumetric density (SVD), renal corpuscle histometric measures, and hemosiderin and lipofuscin deposit frequency in macrophages melanogenic (MMs) were assessed. No biometric differences were observed between the sexes, but body weight and standard length were correlated with RSI. The SVD showed difference in hematopoietic tissue between female and males, whereas the density of the other structures was not different. The RSI was positively associated with hematopoietic tissue and proximal tubule density in contrast to distal tubules, blood vessels, collecting ducts and MMs. Females exhibited a higher renal corpuscle area, glomerulus area, distal tubule diameter, collecting tubule area, and collecting tubule lumen area. These differences may be due to metabolic differences between males and females. Sex effect in P. nattereri may define punctual differences in future studies on the metabolism and immunity of this species.

Polystyrene microparticles can affect the health status of freshwater fish – Threat of oral microplastics intake

Plastic waste pollution is considered one of the biggest problems facing our planet. The production and use of these materials has led to huge amounts of plastic waste entering the aquatic environment and affecting aquatic life. In our experiment, the effect of polystyrene microparticles (PS-MPs; 52.5 ± 11.5 μm) on individual juvenile rainbow trout (Oncorhynchus mykiss) was tested at three different dietary concentrations of 0.5, 2 and 5 % for six weeks. At the end of the experiment, various health parameters of exposed organisms were compared with the control group. The haematological profile revealed an immune response by a decrease in lymphocyte count with a concurrent increase in the number of neutrophil segments at the highest concentration of PS-MPs (5 %). Biochemical analysis showed significant reductions in plasma ammonia in all tested groups, which may be related to liver and gill damage, as determined by histopathological examination and analysis of inflammatory cytokines expression. In addition, liver damage can also cause a significant decrease in the plasma protein ceruloplasmin, which is synthesized in the liver. PS-MPs disrupted the antioxidant balance in the caudal kidney, gill and liver, with significant changes observed only at the highest concentration. In summary, PS-MPs negatively affect the health status of freshwater fish and represent a huge burden on aquatic ecosystems.

Paeonol increases the antioxidant and anti-inflammatory capacity of gibel carp (Carassius auratus gibelio) challenged with Aeromonas hydrophila

Paeonol, a naturally occurring polyphenol isolated from medical plant, has been known to exhibit anti-oxidative and anti-inflammatory effects. In order to evaluate the effect of paeonol on Carassius auratus gibelio infected by pathogenic bacteria Aeromonas hydriphila. 750 fish were randomly divided into 5 groups, which separately treated with 0.85% sterile saline (blank), A. hydriphila (negative control), A. hydriphila with paeonol (4 mg/kg, 64 mg/kg), and A. hydriphila with enrofloxacin (12 mg/kg, positive control). Fish were anaesthetized with MS-222 (100 mg/L), and samples were collected at 6 and 72 h after A. hydriphila challenge. The results showed that compared with the negative group, the survival in paeonol groups marked increased by 14.75% and 18.94%. The plasma immunoglobulin M (IgM) was notably increased, and low density lipoprotein (LDL) was significantly decreased in paeonol groups at 6 h (P < 0.05). The antioxidative enzymes catalase (CAT), total antioxidant capacity (T-AOC) and glutathione peroxidase (GSH-Px) were significantly increased in paeonol groups at 6 h, while malondialdehyde (MDA) and myeloperoxidase (MPO) contents were lower (P < 0.05). The inflammatory related genes MyD88 and TLR-5 were significantly downregulated, and the TLR-3 was significantly increased in paeonol groups at 72 h (P < 0.05). In addition, histopathological analyses showed that the lesion in liver, spleen and caudal kidney were considerably attenuated in paeonol groups. In conclusion, paeonol could increase the survival rate, mitigate oxidative damage, inflammation, tissue lesions, and improve the immunity of gibel carp challenged with A. hydrophila.

Foodborne fluoxetine impacts the immune response in rainbow trout (Oncorhynchus mykkis)

The aim of this study was to reveal the effects of foodborne fluoxetine on morphological and condition profile, hematological profile, biochemical and oxidative stress indices on juvenile rainbow trout. The study was performed according to OECD Guideline No. 215. Fluoxetine was incorporated into Biomar 921 pellets at a dose of 0.047 mg/kg (environmental concentration), 0.577 mg/kg and 6.7 mg/kg. There was statistically significant change in hematological profile, including an increasing trend in neutrophil/lymphocyte ratio and a decreasing trend in the number of lymphocytes. Measurements of oxidative stress indicated decreased activity of the detoxifying enzyme glutathione-S-transferase in the liver and kidney. However, the measurement of GR, GPx, CAT, SOD activity, and TBARS showed no changes. Histopathological examination revealed damage to the proximal tubules of caudal kidney in exposed groups. This study confirms that fluoxetine has a significant effect on immune response.

Combined effect of florfenicol with linalool via bath in combating Aeromonas hydrophila infection in silver catfish (Rhamdia quelen)

The phytochemical linalool has synergistic activity with florfenicol against Aeromonas hydrophila in an in vitro study. However, there is a lack of in vivo studies to confirm this finding. Therefore, the aim of this study was to evaluate the in vivo effect of the combination of florfenicol with linalool via bath against aeromonosis in silver catfish (Rhamdia quelen) and their responses in redox balance and histology of gills, liver, and caudal kidney. In a previous test, a survival curve of silver catfish infected with A. hydrophila and treated with different concentrations of florfenicol via bath was performed. Florfenicol via bath at low concentration (12 mg/L) was able to increase the survival of infected fish. In the main test, the combined effect of florfenicol with linalool was evaluated. Bath with both substances decreased thiobarbituric acid reactive substances - TBARS levels and prevented histological alterations in gills and liver of infected fish. However, the use of these substances via bath was not able to modify the changes observed in other parameters related to the redox balance of infected fish. There was still a satisfactory concentration of linalool 1 d after the bath. In general, the use of florfenicol with linalool would be an appropriate combination for treatment of fish aeromonosis.

Could the Musk Compound Tonalide Affect Physiological Functions and Act as an Endocrine Disruptor in Rainbow Trout?

In the present study, the effect of polycyclic musk compound tonalide (AHTN) in two concentrations was studied in male rainbow trout (Oncorhynchus mykiss, Walbaum 1792). A feeding trial was conducted with AHTN incorporated into feed granules. One concentration was environmentally relevant (854 µg/kg); the second one was 10× higher (8699 µg/kg). The fish were fed twice a day with the amount of feed at 1 % of their body weight. After an acclimatization period, the experimental phase in duration of six weeks followed. At the end of the experiment, fish were sampled and the biometrical data were recorded. Subsequently, hematological and biochemical tests, histopathological examination, analysis of oxidative stress markers and evaluation of endocrine disruption using plasma vitellogenin were performed. In conclusion, an increase of hematocrit for both AHTN concentrations was found, but no significant changes were observed in biochemical profile. Moreover, AHTN caused lipid peroxidation in caudal kidney tissue, which was confirmed by histopathological images. The long-lasting AHTN exposure could thus be harmful for maintaining homeostasis in the rainbow trout organism. However, the vitellogenin concentration seemed not to be affected by AHTN.

The effect of foodborne sertraline on rainbow trout (Oncorhynchus mykiss)

The worldwide consumption of antidepressants is raising as well as their concentrations in the aquatic environment. This increases the risk of food chain contamination and bioaccumulation in aquatic biota. The aim of this study was to describe a potential risk of sertraline as a pollutant from water environment, wherein rainbow trout (Oncorhynchus mykiss) has been chosen as the test organism, because predatory fish are on the top of the food chain in the aquatic environment. The effects of foodborne sertraline were tested on rainbow trout during a 28-day toxicity test according to OECD 215 method. Sertraline was incorporated in commercial feed at a dose of 4.4 µg/kg (environmental concentration), 42 µg/kg and 400 µg/kg. The results confirmed that sertraline has a significant effect on fish behaviour, resulting in suppression of the escape reflex and increased resistance to stress. Moreover, increased Fultońs condition factor was found in fish fed with the highest concentration of sertraline. Haematological analysis revealed a statistically significant increase in the number of neutrophilic bands and neutrophil/lymphocyte ratio, and decreased number of lymphocytes. The results of biochemical examination showed a statistically significant decrease in ammonia and lactate concentrations and histological examination revealed changes in gills and caudal kidney. Although sertraline reduces stress in fish, the decline in nonspecific immunity is a risk to fish population stability.

Expression Patterns of Three Regulatory Genes in Caudal Fin Regeneration of the Euryhaline Killifish, Aphanius hormuzensis (Teleostei: Aphaniidae)

Recent studies indicated that regeneration speed in caudal fin and kidney of the genus Aphanius is faster than the other traditional model zebrafish. Therefore, non-traditional model organisms, such as members of the genus Aphanius, can probably be suitable candidate to study regeneration phenomenon. In order to advance our knowledge on the regeneration ability in the genus Aphanius, firstly we investigated the histology organization of caudal fin regeneration process in ten individuals of Aphanius hormuzensis with 3.5–4.0 cm in total length. In addition, transcription of three controlling genes, i.e., the ligand (Eda) and the receptor (Edar) from ectodysplasin signaling pathway and mmp9 (matrix metallopeptidase 9), were examined during the caudal fin regeneration stages in Aphanius hormuzensis. For the later experiment, 55–60 fish specimens were used to obtain 50 mg tissue for each regeneration stages. Thereafter, the expression patterns of these genes were examined by quantitative real-time PCR. Our histological observations showed three distinct stages in caudal fin regeneration including a wound healing in 24 h post-amputation (hpa), the blastema formation in 72 hpa and the outgrowth with fin ray formation in 5 days post-amputation (dpa). The results of quantitative real-time PCR showed that mmp9 has a strong upregulation during the stages of blastema and fin ray formation. The Eda transcript level was significantly increased, and it has upregulation during the fin ray formation stage. Slight down-regulation of Edar transcripts was observed at the blastema stage, but it was upregulated thereafter. It is documented that ectodysplasin signaling has critical role in morphogenesis of ectodermal appendages, and mmp9 involves in the extracellular matrix remodeling during regeneration. As conclusion, Eda signaling is present and involve in different stages of the caudal fin regeneration in A. hormuzensis. Eda gene upregulation might support the hypothesis that the regulation of Eda/Edar signaling was controlled by the ligand (Eda) expression during the caudal fin regeneration of the studied killifish. Moreover, the upregulation of mmp9 in different stages of regeneration is consistent with its role in the removal of damaged cartilage matrix.

Aroclor 1254 inhibits vasotocinergic pathways related to osmoregulatory and stress functions in the gilthead sea bream (Sparus aurata, Linnaeus 1758)

The present study assesses the response of vasotocinergic system in the gilthead sea bream (Sparus aurata) after administering two doses of the polychlorinated biphenyl Aroclor 1254 (15 or 50 μg g−1 fresh body mass). Seven days post-administration, eight fish of each experimental group were sampled, and the remaining animals were challenged with a hyperosmotic stress by being transferred from seawater (36 ppt) to high salinity water (55 ppt) and being sampled 3 days post-transfer. Aroclor 1254 affected gene expression of avt, together with Avt concentrations in pituitary and plasma, inhibiting the stimulation observed in vasotocinergic system after hyperosmotic challenge. This was noted by the accumulation of Avt at hypophyseal level as well as by its undetectable values in plasma. Hyperosmotic transfer significantly changed branchial avtrv1a, avtrv2, atp1a and cftr mRNA expression levels in control fish, while in Aroclor 1254-treated fish they remained mostly unchanged. This desensitization also occurred for avtrs in hypothalamus, caudal kidney and liver. In addition, an enhancement in plasma cortisol concentration, together with the orchestration of several players of the Hypothalamic-Pituitary-Interrenal axis (crh, crhbp, trh, star), was also observed mostly at the highest dose used (50 μg g−1 body mass), affecting plasma and hepatic metabolites. Our results demonstrated that Aroclor 1254 compromises the hypoosmoregulatory function of vasotocinergic system in S. aurata, also inducing a concomitant stress response. In summary, this study demonstrates that Aroclor 1254 can be considered an important endocrine disruptor in relation with the correct arrangement of vasotocinergic, metabolic and stress pathways after their stimulation by transfer to hyperosmotic environments.

Bioinformatic analysis of antivirus‐related TRIM genes in Dabry’s sturgeon Acipenser dabryanus

TRIM proteins are a group of highly conserved proteins that participate in a variety of biological processes in innate immunity. However, the roles of the Acipenseridae trim genes in the anti-bacterial immune response remained uncertain. In the present study, the Dabry’s sturgeon (Acipenser dabryanus) TRIM2, TRIM8, and TRIM59 protein sequences were found to be similar to Chicken (Gallus gallus), with identities 92.8%, 89.1%, and 79.4%, respectively. Meanwhile, the TRIM23, TRIM37, and TRIM82 proteins shared 95.8%, 81.7%, and 78.1% similarity with Zebrafish (Danio rerio) homologs, respectively. Sequence alignment indicated that these six adTRIMs contained incomplete domains at their N-termini, including a RING-finger domain and one or two B-boxes domains. The six adtrim genes were constitutively expressed in immune related tissues, such as the head kidney, and were also expressed in non-immune related tissues, like the blood, brain, muscle, and liver. After challenge with Aeromonas hydrophila, the expression levels of adtrims changed during the early stage of infection. Stimulation by A. hydrophila upregulated the expression levels of adtrim8 and adtrim59 in the spleen and caudal kidney, while the expression of adtrim82 in the spleen and caudal kidney was inhibited at 12 hr post-infection. A. hydrophila challenge led to significant upregulation of adtrim2 and downregulation of adtrim23 in the spleen. In addition, adtrim37 was only weakly affected by A. hydrophila stimulation. These results suggested that adtrims were related to the immune response to bacterial infection, which provides the fundamental basis for protecting Dabry’s sturgeon against pathogen attack.

First Study on Interferon Regulatory Factor in Sturgeon: Expression Pattern of Interferon Regulatory Factor in Dabry's Sturgeon Acipenser dabryanus.

Interferon regulatory factors (IRFs) are crucial regulators in initiating the host innate immune response against pathogen invasions. Dabry's sturgeon (Acipenser dabryanus) is particularly a valuable fish species found in the Yangtze River, China for which there is scarce immunological data. In the present study, we investigated the expression profile of sturgeon IRF genes. All adIRFs were composed of 8 exons and 7 introns, except adIRF1, which possessed 9 exons interrupted by 8 introns. Moreover, the predicted protein sequence has a DNA-binding domain (DBD) sharing high identity with spotted gar (Lepisosteus oculatus). Regarding the expression patterns, 5 adIRF genes were found to be constitutively expressed in all tissues examined, and were significantly higher in lymphoid organs (eg, blood, kidney, intestine, and spleen). Following Aeromonas hydrophila infection, the expression of adIRF1 and adIRF3 were upregulated in the spleen and caudal kidney, while both the adIRF5 and adIRF8 genes were downregulated in caudal kidney. In addition, adIRF4 was significantly upregulated at 3 h postinfection by A. hydrophila in the spleen and caudal kidney. These results suggest that adIRFs are related to the immune response to bacterial infection, which will help clarify the function of these IRFs and provide a fundamental basis for protecting the Dabry's sturgeon.

Effects of selected tricyclic antidepressants on early-life stages of common carp (Cyprinus carpio)

Despite the fact that pharmaceuticals occur in surface water in low concentrations, they can still have adverse effect on aquatic biota, because these substances are designed to have a specific mode of action even at low concentrations. To our knowledge, only little is known about the long-term effect of tricyclic antidepressant residues on non-target animals, especially fish. Hence, the aim of this study was to assess the effect of subchronic exposure to selected tricyclic antidepressants – namely, amitriptyline, nortriptyline, and clomipramine and their mixture – on early-life stages of common carp (Cyprinus carpio). Two embryo-larval toxicity tests with common carp were performed, each taking 30 days. For the experiment, three tricyclic antidepressants as well as their mixtures were tested at three different concentrations – 10, 100 and 500 μg/L. Hatching and mortality were recorded twice a day. In addition, samples were taken at regular intervals in order to record developmental stage, morphometric and condition characteristics and morphological anomalies. At the end of the test, additional samples were taken for histopathological examination and also for the determination of antioxidant and biotransformation enzyme activity and lipid peroxidation and protein carbonylation. Long-term exposure resulted in a significant increase in mortality, developmental retardation, morphological anomalies, and pathological changes in brain, heart, and cranial and caudal kidney. In addition, changes in antioxidant enzyme activity as well as increased lipid peroxidation were observed, even at the lowest tested concentrations. Hence, environmentally relevant concentrations of TCAs have the potential to cause harmful effects on early-life stages of fish.

Prone Percutaneous Nephrolithotomy: Does Bolster Orientation Matter?

To assess whether horizontal vs vertical bolster orientation affects kidney position during prone percutaneous nephrolithotomy as this could impact the need for supracostal access and therefore the likelihood of pleural injury. In a prospective trial, 10 subjects with 20 renal units underwent magnetic resonance imaging in prone position with standard cylindrical bolsters oriented vertically and then horizontally. Vertical bolsters were placed along the lateral aspect of the chest. Horizontal bolsters were placed at the xiphoid and symphysis pubis. The position of the kidney relative to the pleura was assessed by measuring distances from the kidney upper pole to diaphragm, to the top of the first lumbar vertebra, and inferior-most rib. Nephrostomy tract length and tract proximity to adjacent organs were also measured. Right and left kidney-to-diaphragm distance significantly increased with horizontal vs vertical bolsters by 3.44 cm and 1.86 cm, respectively (P = .02, P = .01). Right kidney-to-rib distance significantly increased by 2.4 cm (P = .025); left kidney-to-rib distance increased by 0.5 cm (P = .123). Right kidney-to-vertebral distance significantly increased by 2.16 cm (P = .007); left kidney-to-vertebral distance increased by 0.9 cm (P = .059). There was no significant difference in maximum access angle, overall tract length, or colon position between horizontal and vertical bolsters. Orienting bolsters horizontally results in caudal kidney displacement without affecting access angle, overall tract length, or colon position. In comparison with vertical orientation, this may improve safety of percutaneous nephrolithotomy by decreasing the need for supracostal access and increasing the safety of supracostal access when required.

Effect of T-2 toxin-contaminated diet on common carp (Cyprinus carpio L.)

The T-2 toxin, a fungal metabolite produced by Fusarium molds, occurs in a range of agriculture products. Reduced availability of fish meal has led to increasing use of cereals as a source of protein in commercial aquaculture feeds, which has increased the potential for mycotoxin contamination. The purpose of this study was to investigate toxicity of T-2 toxin intake in common carp (Cyprinus carpio L.) using haematological, biochemical and immunological parameters and oxidative stress indices. In a four-week feeding trial, fish were fed a commercial diet with 5.3 mg/kg T-2 toxin added. Ingestion of contaminated diet did not lead to mortality of fish, probably due to lower feed intake. On the other hand, it significantly affected haematological variables such as haematocrit, haemoglobin, red blood cell counts leading to anemia and white blood cell counts leading to leukopenia due to lymphopenia. Plasma glucose concentration and alanine amino transferase activity showed a significant increase while triglycerides concentration decreased. Activity of ceruloplasmin was significantly decreased in plasma. Further, liver glutathione S-transferase activity was significantly increased and catalase activity decreased, in parallel with a significant increase in caudal kidney catalase activity and a decrease in glutathione peroxidase activity. Finally, lipid peroxidation (detected as malondialdehyde) was significantly increased in the liver and caudal kidney. Changes in non-specific immune response and cytokine levels in head kidney indicated immune system sensitivity to T-2 toxin. Overall, the results demonstrate that this feed-borne mycotoxin is able to induce anaemia and oxidative stress and cause changes in the immune response of common carp.

Abnormal Buoyancy in a Convict Cichlid (Amatitlania Nigrofasciata) Associated With an Ovarian Carcinoma Invading the Swim Bladder

An 8-year-old female convict cichlid (Amatitlania nigrofasciata) was presented to the University of Wisconsin Veterinary Medical Teaching Hospital with a 2-month history of abnormal buoyancy; the fish spent most of its time in lateral recumbency on the aquarium substrate. During the initial visual examination of the patient in its transport aquarium, the fish was laterally recumbent on the bottom of the tank and had a mildly distended coelom. A transient response to empirical florfenicol therapy was reported, but the cichlid presented 1 month later in poor body condition and, again, in lateral recumbency. Owing to the poor prognosis, the fish was humanely euthanized and a necropsy was performed. The histopathologic results were consistent with a papillary carcinoma originating in the ovary, which invaded the caudal kidney and the swim bladder. The infiltration of the carcinoma into the swim bladder was suspected to be the primary cause of the clinically observed buoyancy abnormality.

Sequence and Expression Analysis of Interferon Regulatory Factor 10 (IRF10) in Three Diverse Teleost Fish Reveals Its Role in Antiviral Defense.

BackgroundInterferon regulatory factor (IRF) 10 was first found in birds and is present in the genome of other tetrapods (but not humans and mice), as well as in teleost fish. The functional role of IRF10 in vertebrate immunity is relatively unknown compared to IRF1-9. The target of this research was to clone and characterize the IRF10 genes in three economically important fish species that will facilitate future evaluation of this molecule in fish innate and adaptive immunity.Molecular Characterization of IRF10 in Three Fish SpeciesIn the present study, a single IRF10 gene was cloned in grass carp Ctenopharyngodon idella and Asian swamp eel Monopterus albus, and two, named IRF10a and IRF10b, in rainbow trout Oncorhynchus mykiss. The fish IRF10 molecules share highest identities to other vertebrate IRF10s, and have a well conserved DNA binding domain, IRF-associated domain, and an 8 exon/7 intron structure with conserved intron phase. The presence of an upstream ATG or open reading frame (ORF) in the 5’-untranslated region of different fish IRF10 cDNA sequences suggests potential regulation at the translational level, and this has been verified by in vitro transcription/translation experiments of the trout IRF10a cDNA, but would still need to be validated in fish cells.Expression Analysis of IRF10 In Vivo and In VitroBoth trout IRF10 paralogues are highly expressed in thymus, blood and spleen but are relatively low in head kidney and caudal kidney. Trout IRF10b expression is significantly higher than IRF10a in integumentary tissues i.e. gills, scales, skin, intestine, adipose fin and tail fins, suggesting that IRF10b may be more important in mucosal immunity. The expression of both trout IRF10 paralogues is up-regulated by recombinant IFN-γ. The expression of the IRF10 genes is highly induced by Poly I:C in vitro and in vivo, and by viral infection, but is less responsive to peptidoglycan and bacterial infection, suggesting an important role of fish IRF10 in antiviral defense.